The invention relates to method and apparatus for measuring changes in the elasticity of materials, particularly elastomers used for gaskets, seals, and the like, particularly in situ measurements.
The elasticity of a material is an important property and its loss or degradation can have serious consequences, ranging from changes in mechanical or electrical properties to catastrophic failure. The industrial and military use of elastic materials for gaskets and seals is ubiquitous. The gasket and sealant materials are typically subjected to extraordinary variations in stress, vibration, temperature, and exposure to various chemical agents, which lead to eventual degradation of elasticity and failure of the materials. In most situations, gasket and sealant failure can lead to costly maintenance, and prolonged downtime if the failure is not rapidly detected or anticipated. In the extreme case, gasket or seal failure can have catastrophic results, as evidenced by the space shuttle disaster.
Currently, there are no convenient or practical means for in situ monitoring of the state of elastomer degradation in gaskets, seals, or the like, when used in industrial equipment or vehicles. In particular, because in situ monitors are currently not available, either the gasket or sealant materials must be removed from the equipment for inspection and testing, or the materials must be routinely replaced at intervals determined by theoretical estimates of failure times.
Clearly the availability of an inexpensive in situ monitor of gasket and sealant elasticity would result in significant savings in time and money by eliminating unnecessary maintenance, and by avoiding the consequences of unanticipated failures of the gasket or sealant materials.